Merged r12424 from trunk to 2.4-stable.

fix svn raw diff failure on svn version 1.6.17 (revision 1128011).

git-svn-id: http://svn.redmine.org/redmine/branches/2.4-stable@12425 e93f8b46-1217-0410-a6f0-8f06a7374b81